WASHINGTON (AP) — Divided Republicans are convening the House this weekend in hopes of preventing a federal government shutdown but remain under pressure from the party's conservative wing to battle on and try to derail all or part of President Barack Obama's health care law.

The weekend session comes after the Senate on Friday sent back to the House legislation to keep the government's doors open until Nov. 15, but only after Democrats stripped from the bill a provision to defund the Affordable Care Act, also called Obamacare.

Congress faces a midnight deadline on Monday. Failure to pass a short-term funding bill by then would mean the first partial government shutdown in almost 20 years.

The Senate's 54-44 vote was strictly along party lines in favor of the bill, which would prevent a shutdown of nonessential government services.

That tally followed a 79-19 vote to cut off a filibuster by Republican Sen. Ted Cruz, which exposed a rift among Republicans eager to prevent a shutdown and those, like Cruz, who seem willing to risk one over derailing the health care law.

All 52 Democrats, two independents and 25 of 44 Republicans voted in favor. That included Minority Leader Mitch McConnell and most of the Republican leadership.

Cruz was whipping up House conservatives to continue the battle over Obamacare, urging them to reject efforts by Speaker John Boehner and other Republican leaders to offer scaled-back assaults on the law like repealing a tax on medical devices as the House response.

Some conservatives were taking their cues from Cruz rather than Republican leaders like Boehner hoping to avoid a shutdown, especially one that could weaken Republicans heading into an even more important battle later in October over allowing the government to borrow more money.

"I am confident the House of Representatives will continue to stand its ground, continue to listen to the American people and ... stop this train wreck, this nightmare that is Obamacare," Cruz said.

Republican leaders had yet to announce a plan heading into an emergency meeting Saturday afternoon of House Republicans. A vote on the as-yet-unwritten measure seemed most likely on Sunday, leaving little time for the Senate to respond on Monday.

Democratic Majority Leader Harry Reid warned that the Senate will not accept any House measure that contains provisions opposed by Democrats. And he knows better than anyone that any single senator could slow down the Senate's ability to ping-pong yet another version back to the House.

"This is it. Time is gone," Reid said in a warning to Republicans. "They should think very carefully about their next steps. Any bill that continues to play political games will force a government shutdown."

Late on Friday, more than five dozen conservatives rallied behind an amendment by Republican Rep. Tom Graves to delay Obamacare through the end of next year. It's a nonstarter with the Senate.

If lawmakers blow the deadline, hundreds of thousands of nonessential federal workers would have to stay home on Tuesday, though critical services like patrolling the borders, inspecting meat and controlling air traffic would continue. Social Security benefits would be sent and the Medicare and Medicaid health care programs for the elderly and poor would continue to pay doctors and hospitals.

Also on Tuesday, Obamacare insurance exchanges would open, a development that's lent urgency to the drive to use a normally routine stopgap spending bill to gut implementation of the health care law.

"I'm more concerned about the impact of this law on the American people than I am about my re-election," said freshman Republican Rep. Richard Hudson.

But party veterans warn that the political risk of a shutdown is simply too great.


Associated Press writer Josh Lederman contributed to this report.